by Judith Valente, Special for USA TODAY

by Judith Valente, Special for USA TODAY

CHICAGO - For more than 30 years, Sherry Marino faithfully placed flowers and candles at the grave that bore the name of her 14-year-old son, Michael, identified as one of the victims of notorious serial killer John Wayne Gacy.

But each time she stood at the grave site, she felt a nagging suspicion that she had buried some other mother's son. "It was just a feeling you get when you're a mother. I'd put my hand on the grave and I'd feel cold. I didn't feel it was Michael in there," Marino says.

Last fall, Marino obtained a court order to exhume Michael's body and put her doubts to scientific scrutiny. Preliminary DNA tests show her mother's instincts were correct: The remains in the casket weren't Michael's.

"I always knew it. I said to everyone, you're going to see that I'm right," she said recently in her first newspaper interview since the DNA results became available.

Those results pose one more challenge for authorities, who are still trying to identify some of Gacy's victims nearly two decades after his execution in 1994. Known as the "Killer Clown" because he often portrayed a clown at charity events, Gacy was convicted of killing 33 young men or boys in the 1970s.

So if he wasn't one of Gacy's victims, what happened to Michael, a talented drummer who loved Led Zeppelin and dreamed of becoming a professional musician? He disappeared in 1976 and would have been 51 today.

"I'm saying my son is still somewhere out there," Marino says.

Marino was skeptical from the start when authorities took 15 months to identify Michael as Victim No. 14, even though Marino provided her son's dental records shortly after Gacy was arrested. The remains were pulled from a crawl space in Gacy's home in the Chicago suburb of Norwood Park Township. DNA testing did not exist at the time, and identifications were made largely through dental records and X-rays.

Some of the clothing on the body didn't match what Marino remembered her son wearing on the day he went missing. An entry in the autopsy report also noted that Michael's collarbone had healed from a previous injury. Marino said her son had never suffered a broken collarbone.

TEST RESULTS IN DISPUTE

Despite the DNA analysis showing the remains aren't Michael's, the Cook County Sheriff's Office has refused to accept the test results.

Sheriff's Detective Jason Moran said Marino's attorneys provided investigators with a "redacted and incomplete" report on the test which "does not allow for competent review or conclusion."

The sheriff's office wants a lab it normally uses at the University of North Texas to repeat the test.

"I sympathize with Mrs. Marino, I really do," said Cook County Sheriff Thomas Dart. "But a death certificate has been issued in the name of Michael Marino, and we simply cannot change it without legitimate evidence from a credible DNA test."

"Mrs. Marino isn't seeking a government-stamped piece of paper," said Steven Becker, one of her attorneys. "She is seeking her son."

Dart said that if a second test confirms that Michael's remains were misidentified, "we will try to find out whose DNA it is, and what happened to this boy who has been missing for over 30 years."

Marino last saw Michael on Oct. 24, 1976. "It was a Sunday, at 2 o'clock in the afternoon," she recalls with precision. "He made me a sandwich and said 'Mom, I'm going to the game room,'" a popular pinball arcade in a neighborhood where Gacy often trolled for victims.

Michael and his mother made plans to see a movie together that evening. "Then he kissed me on my cheek and went off," she said.

When Michael didn't return home, Marino says, she "went from worried to frantic." She contacted the police, who told her Michael probably had run away. "They said it's what teenage boys do. I said, 'You don't know my son.'"

For more than three years, Marino searched on her own for Michael, her middle child and only son. She posted his photograph in storefronts. She even forced her way into well-known drug houses, fearing Michael may have fallen in with the wrong crowd.

"I would push my way through doorways where people were getting high. I would say, 'I'm looking for my son.'" She spent thousands of dollars to hire private investigators.

TRAGIC NEWS ARRIVES

The dreaded news came in March 1980. Marino says two police officers arrived at her door and told her that authorities had made "an awfully big mistake" in treating Michael as a runaway.

Police said Michael had been identified as one of the bodies discovered months earlier in Gacy's house. They said the previously unidentified body found lying next to Michael was that of 16-year-old Kenneth Parker, the friend who had accompanied Michael to the pinball arcade on the day he went missing.

"I fell to my knees, just passed out," she recalls.

Marino has refused to give sheriff's investigators a saliva swab of her DNA, saying she has lost confidence in the authorities. However, she says she would be willing to submit another sample to a laboratory not currently affiliated with the sheriff's department or the Chicago police.

Edward Pavlik, the orthodontist who headed the team that identified Gacy victims, says he has no doubt that Michael was murdered by Gacy.

Pavlik said Michael's remains were examined in 1980 by a team of four forensic odontologists. They used both dental charts and X-rays of fillings, which carry unique characteristics similar to a fingerprint, to make the identification. A radiologist examined the skeletal remains and also concluded they belonged to Michael.

After the Marino identification was called into question, three additional forensic odontologists reviewed the dental records, Pavlik said. Those experts reached the same conclusion as the original team.

Pavlik said there is a "remote possibility" Michael's remains were mixed up with someone else's after the identification was made. "But I don't think realistically that's what happened."

He said it is possible that the laboratory that did the analysis for Marino used "faulty" procedures to procure DNA from the bones in the casket, or else compared those samples with Marino's DNA "inaccurately."

Marino, 69 and suffering from several ailments, continues to hope for closure.

"It's like living in limbo continuously," she says. "It's changed me in every way. I don't trust anyone. I believe very little of what I hear."

Although she recognizes there is only a remote possibility that Michael is still alive, she says, "I have hope. I have a lot of hope. I would love to be able to hold him again."